Press Association Sport understands Mackay will not resign from his post, despite seeing one of his most-trusted aides suspended and subsequently placed on gardening leave, but the move has put his position under scrutiny.
Cardiff's Malaysian owner Vincent Tan has handed Moody's duties on an acting basis to 23-year-old Kazakhstani Alisher Apsalyamov.
Apsalyamov is thought to be a friend of Tan's son and appears to have no previous experience in football.
He joined the club in February but his name does not appear on a list of key staff members on the club's official website.
Tan previously caused consternation among Bluebirds' fans by changing the club's playing kit from blue to red and heavily altering their crest in 2012.
It has also been reported Tan asked Mackay to resign on Tuesday, Cardiff were unavailable to comment when contacted by Press Association Sport on the subject.
And the Supporters' Trust are concerned the club could lose their highly-rated and popular Scottish boss.
"Supporters are surprised that who appears to have little hands-on experience has been put in charge of transfers at the football club.